diff --git a/package.json b/package.json
index 965db511..a9800080 100644
--- a/package.json
+++ b/package.json
@@ -74,8 +74,8 @@
     "@types/mime-types": "^3.0.1",
     "@types/morgan": "^1.9.10",
     "@types/node": "22.19.19",
-    "@types/react": "^18.3.29",
-    "@types/react-dom": "^18.3.7",
+    "@types/react": "^19.2.15",
+    "@types/react-dom": "^19.2.3",
     "@types/react-syntax-highlighter": "^15.5.13",
     "@types/semver": "^7.7.1",
     "@types/smpte-timecode": "^1.2.5",
@@ -114,11 +114,11 @@
     "p-map": "^7.0.4",
     "p-retry": "^8.0.0",
     "pretty-bytes": "^7.1.0",
-    "react": "^18.3.1",
-    "react-dom": "^18.3.1",
+    "react": "^19.2.6",
+    "react-dom": "^19.2.6",
     "react-i18next": "^17.0.8",
     "react-icons": "^5.6.0",
-    "react-leaflet": "^4.2.1",
+    "react-leaflet": "^5.0.0",
     "react-lottie-player": "^2.1.0",
     "react-markdown": "^10.1.0",
     "react-syntax-highlighter": "^16.1.1",
diff --git a/src/renderer/src/App.tsx b/src/renderer/src/App.tsx
index 8c532c69..b77637b3 100644
--- a/src/renderer/src/App.tsx
+++ b/src/renderer/src/App.tsx
@@ -167,7 +167,7 @@ function App() {
 
   // State per application launch
   const [ffmpegInfo, setFfmpegInfo] = useState<Awaited<ReturnType<typeof runStartupCheck>>>();
-  const lastOpenedPathRef = useRef<string>();
+  const lastOpenedPathRef = useRef<string>(undefined);
   const [showRightBar, setShowRightBar] = useState(true);
   const [lastCommandsVisible, setLastCommandsVisible] = useState(false);
   const [settingsVisible, setSettingsVisible] = useState(false);
@@ -372,7 +372,7 @@ function App() {
   const segmentsAtCursor = useMemo(() => findSegmentsAtCursor(commandedTime).map((index) => cutSegments[index]), [commandedTime, cutSegments, findSegmentsAtCursor]);
   const firstSegmentAtCursor = useMemo(() => segmentsAtCursor[0], [segmentsAtCursor]);
 
-  const segmentAtCursorRef = useRef<StateSegment>();
+  const segmentAtCursorRef = useRef<StateSegment>(undefined);
   useEffect(() => {
     segmentAtCursorRef.current = firstSegmentAtCursor;
   }, [firstSegmentAtCursor]);
diff --git a/src/renderer/src/MediaSourcePlayer.tsx b/src/renderer/src/MediaSourcePlayer.tsx
index 9f7fb5a2..af57036a 100644
--- a/src/renderer/src/MediaSourcePlayer.tsx
+++ b/src/renderer/src/MediaSourcePlayer.tsx
@@ -312,7 +312,7 @@ function MediaSourcePlayer({ rotate, filePath, videoStream, audioStreams, master
   filePath: string,
   videoStream: FFprobeStream | undefined,
   audioStreams: FFprobeStream[],
-  masterVideoRef: RefObject<HTMLVideoElement>,
+  masterVideoRef: RefObject<HTMLVideoElement | null>,
   mediaSourceQuality: number,
   ffmpegHwaccel: FfmpegHwAccel,
 }) {
diff --git a/src/renderer/src/Timeline.tsx b/src/renderer/src/Timeline.tsx
index e4e2a8da..1983569f 100644
--- a/src/renderer/src/Timeline.tsx
+++ b/src/renderer/src/Timeline.tsx
@@ -158,7 +158,7 @@ function Timeline({
 
   const timelineScrollerRef = useRef<HTMLDivElement>(null);
   const timelineScrollerSkipEventRef = useRef<boolean>(false);
-  const timelineScrollerSkipEventDebounce = useRef<() => void>();
+  const timelineScrollerSkipEventDebounce = useRef<() => void>(undefined);
   const timelineWrapperRef = useRef<HTMLDivElement>(null);
 
   const isZoomed = zoom > 1;
@@ -278,7 +278,7 @@ function Timeline({
     return (relX / target.offsetWidth) * fileDurationNonZero;
   }, [fileDurationNonZero]);
 
-  const mouseDownRef = useRef<unknown>();
+  const mouseDownRef = useRef<unknown>(undefined);
 
   useEffect(() => {
     setHoveringTime(undefined);
@@ -290,7 +290,7 @@ function Timeline({
     currentCutSegRef.current = currentCutSeg;
   }, [currentCutSeg]);
 
-  const resizingSegmentRef = useRef<{ operation: 'start' | 'end' | 'move', offset?: number } | undefined>();
+  const resizingSegmentRef = useRef<{ operation: 'start' | 'end' | 'move', offset?: number } | undefined>(undefined);
 
   const onMouseDown = useCallback<MouseEventHandler<HTMLElement>>((e) => {
     if (e.nativeEvent.buttons !== 1) return; // not primary button
diff --git a/src/renderer/src/components/BigWaveform.tsx b/src/renderer/src/components/BigWaveform.tsx
index 3a7e1c14..fd71de64 100644
--- a/src/renderer/src/components/BigWaveform.tsx
+++ b/src/renderer/src/components/BigWaveform.tsx
@@ -28,7 +28,7 @@ function BigWaveform({ waveforms, relevantTime, playing, fileDurationNonZero, zo
 
   const smoothTime = smoothTimeRaw ?? relevantTime;
 
-  const mouseDownRef = useRef<{ relevantTime: number, x: number }>();
+  const mouseDownRef = useRef<{ relevantTime: number, x: number }>(undefined);
   const containerRef = useRef<HTMLDivElement>(null);
 
   const getRect = useCallback(() => containerRef.current!.getBoundingClientRect(), []);
diff --git a/src/renderer/src/components/ExportConfirm.tsx b/src/renderer/src/components/ExportConfirm.tsx
index 68c019d7..62446eb2 100644
--- a/src/renderer/src/components/ExportConfirm.tsx
+++ b/src/renderer/src/components/ExportConfirm.tsx
@@ -149,7 +149,7 @@ function ExportConfirm({
   onClosePress: () => void,
   onExportConfirm: () => void,
   outFormat: string | undefined,
-  renderOutFmt: (style: CSSProperties) => JSX.Element,
+  renderOutFmt: (style: CSSProperties) => ReactNode,
   outputDir: string | undefined,
   numStreamsTotal: number,
   numStreamsToCopy: number,
diff --git a/src/renderer/src/components/PlaybackStreamSelector.tsx b/src/renderer/src/components/PlaybackStreamSelector.tsx
index d6b3dcf3..ccb842e2 100644
--- a/src/renderer/src/components/PlaybackStreamSelector.tsx
+++ b/src/renderer/src/components/PlaybackStreamSelector.tsx
@@ -32,7 +32,7 @@ function PlaybackStreamSelector({
   onActiveAudioStreamsChange: (a: Set<number>) => void,
 }) {
   const [controlVisible, setControlVisible] = useState(false);
-  const timeoutRef = useRef<number>();
+  const timeoutRef = useRef<number>(undefined);
 
   const { t } = useTranslation();
 
diff --git a/src/renderer/src/components/TextInput.tsx b/src/renderer/src/components/TextInput.tsx
index 48de0d3e..6c081a3d 100644
--- a/src/renderer/src/components/TextInput.tsx
+++ b/src/renderer/src/components/TextInput.tsx
@@ -1,11 +1,12 @@
-import type { CSSProperties } from 'react';
-import { forwardRef } from 'react';
+import { forwardRef, type CSSProperties, type InputHTMLAttributes } from 'react';
 
 
+type Props = InputHTMLAttributes<HTMLInputElement> & { style?: CSSProperties };
+
 const inputStyle: CSSProperties = { borderRadius: '.4em', flexGrow: 1, fontFamily: 'inherit', fontSize: '.8em', backgroundColor: 'var(--gray-3)', color: 'var(--gray-12)', border: '1px solid var(--gray-7)', appearance: 'none' };
 
 // eslint-disable-next-line react/display-name
-const TextInput = forwardRef<HTMLInputElement, JSX.IntrinsicElements['input']>(({ style, ...props }, forwardedRef) => (
+const TextInput = forwardRef<HTMLInputElement, Props>(({ style, ...props }, forwardedRef) => (
   // eslint-disable-next-line react/jsx-props-no-spreading
   <input type="text" ref={forwardedRef} style={{ ...inputStyle, ...style }} {...props} />
 ));
diff --git a/src/renderer/src/components/VolumeControl.tsx b/src/renderer/src/components/VolumeControl.tsx
index 33d50ddc..b3f76190 100644
--- a/src/renderer/src/components/VolumeControl.tsx
+++ b/src/renderer/src/components/VolumeControl.tsx
@@ -12,7 +12,7 @@ function VolumeControl({ playbackVolume, setPlaybackVolume, onToggleMutedClick }
   onToggleMutedClick: () => void,
 }) {
   const [volumeControlVisible, setVolumeControlVisible] = useState(false);
-  const timeoutRef = useRef<number>();
+  const timeoutRef = useRef<number>(undefined);
   const { t } = useTranslation();
   const actionTitle = useActionTitle();
 
diff --git a/src/renderer/src/hooks/useContextMenu.ts b/src/renderer/src/hooks/useContextMenu.ts
index 86c13a15..d286f547 100644
--- a/src/renderer/src/hooks/useContextMenu.ts
+++ b/src/renderer/src/hooks/useContextMenu.ts
@@ -7,7 +7,7 @@ import type { ContextMenuTemplate } from '../types';
 
 // https://github.com/transflow/use-electron-context-menu
 export default function useContextMenu(
-  ref: RefObject<HTMLElement>,
+  ref: RefObject<HTMLElement | null>,
   template: ContextMenuTemplate,
 ) {
   const { openMenu, closeMenu } = useNativeMenu(template);
diff --git a/src/renderer/src/hooks/useKeyboard.ts b/src/renderer/src/hooks/useKeyboard.ts
index a1598dff..7192f584 100644
--- a/src/renderer/src/hooks/useKeyboard.ts
+++ b/src/renderer/src/hooks/useKeyboard.ts
@@ -88,12 +88,12 @@ export default ({ keyBindings, keyUpActions, getKeyboardAction, closeExportConfi
 
 
   // optimization to prevent re-binding all the time:
-  const onKeyDownRef = useRef<(a: KeyEventParams) => void>();
+  const onKeyDownRef = useRef<(a: KeyEventParams) => void>(undefined);
   useEffect(() => {
     onKeyDownRef.current = onKeyDown2;
   }, [onKeyDown2]);
 
-  const onKeyUpRef = useRef<(a: KeyEventParams) => void>();
+  const onKeyUpRef = useRef<(a: KeyEventParams) => void>(undefined);
   useEffect(() => {
     onKeyUpRef.current = onKeyUp2;
   }, [onKeyUp2]);
diff --git a/src/renderer/src/hooks/useKeyframes.ts b/src/renderer/src/hooks/useKeyframes.ts
index 8758a874..97d39aa9 100644
--- a/src/renderer/src/hooks/useKeyframes.ts
+++ b/src/renderer/src/hooks/useKeyframes.ts
@@ -27,7 +27,7 @@ function useKeyframes({ keyframesEnabled, filePath, commandedTime, videoStream,
 }) {
   const { t } = useTranslation();
 
-  const readingKeyframesPromise = useRef<Promise<unknown>>();
+  const readingKeyframesPromise = useRef<Promise<unknown>>(undefined);
   const [neighbouringKeyFramesMap, setNeighbouringKeyFrames] = useState<Record<string, Frame>>({});
 
   const neighbouringKeyFrames = useMemo(() => Object.values(neighbouringKeyFramesMap), [neighbouringKeyFramesMap]);
diff --git a/src/renderer/src/hooks/useSegmentsAutoSave.ts b/src/renderer/src/hooks/useSegmentsAutoSave.ts
index e5cc4a2b..bb139ab5 100644
--- a/src/renderer/src/hooks/useSegmentsAutoSave.ts
+++ b/src/renderer/src/hooks/useSegmentsAutoSave.ts
@@ -32,7 +32,7 @@ export default ({ autoSaveProjectFile, storeProjectInWorkingDir, filePath, custo
   // NOTE: Could lose a save if user closes too fast, but not a big issue I think
   const [debouncedSaveOperation] = useDebounce(currentSaveOperation, isDev ? 2000 : 500);
 
-  const lastSaveOperation = useRef<typeof debouncedSaveOperation>();
+  const lastSaveOperation = useRef<typeof debouncedSaveOperation>(undefined);
 
   useEffect(() => {
     async function save() {
diff --git a/src/renderer/src/hooks/useVideo.ts b/src/renderer/src/hooks/useVideo.ts
index 6a964af5..457ea09c 100644
--- a/src/renderer/src/hooks/useVideo.ts
+++ b/src/renderer/src/hooks/useVideo.ts
@@ -9,7 +9,7 @@ export default ({ filePath }: { filePath: string | undefined }) => {
   const [outputPlaybackRate, setOutputPlaybackRateState] = useState(1);
   const [playerTime, setPlayerTime] = useState<number>();
   const [playbackMode, setPlaybackModeState] = useState<PlaybackMode>();
-  const playbackModeRef = useRef<PlaybackMode>();
+  const playbackModeRef = useRef<PlaybackMode>(undefined);
 
   const setPlaybackMode = useCallback((mode: PlaybackMode | undefined) => {
     playbackModeRef.current = mode;
@@ -34,7 +34,7 @@ export default ({ filePath }: { filePath: string | undefined }) => {
 
   // https://kitchen.vibbio.com/blog/optimizing-html5-video-scrubbing/
   const seekingRef = useRef<NodeJS.Timeout | undefined>(undefined);
-  const seekToRef = useRef<number>();
+  const seekToRef = useRef<number>(undefined);
 
   const smoothSeek = useCallback((seekTo: number) => {
     if (seekingRef.current) {
diff --git a/src/renderer/src/hooks/useWaveform.ts b/src/renderer/src/hooks/useWaveform.ts
index 3433507e..aa60cec5 100644
--- a/src/renderer/src/hooks/useWaveform.ts
+++ b/src/renderer/src/hooks/useWaveform.ts
@@ -22,7 +22,7 @@ export default ({ filePath, relevantTime, fileDuration, waveformEnabled, audioSt
 }) => {
   const [waveforms, setWaveforms] = useState<WaveformSlice[]>([]);
   const [overviewWaveform, setOverviewWaveform] = useState<OverviewWaveform>();
-  const waveformsRef = useRef<WaveformSlice[]>();
+  const waveformsRef = useRef<WaveformSlice[]>(undefined);
 
   useEffect(() => {
     waveformsRef.current = waveforms;
diff --git a/yarn.lock b/yarn.lock
index 693ae0ed..cd947150 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3628,14 +3628,14 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@react-leaflet/core@npm:^2.1.0":
-  version: 2.1.0
-  resolution: "@react-leaflet/core@npm:2.1.0"
+"@react-leaflet/core@npm:^3.0.0":
+  version: 3.0.0
+  resolution: "@react-leaflet/core@npm:3.0.0"
   peerDependencies:
     leaflet: ^1.9.0
-    react: ^18.0.0
-    react-dom: ^18.0.0
-  checksum: 10/12ce28b85cf6712a1a7b7c49466b941fc619bc7b1535308bc5711a35f7e89eb16298babfd62f6b3a92e64abf94dcf517b2bc460f59fcf20599821bc6ab3b3048
+    react: ^19.0.0
+    react-dom: ^19.0.0
+  checksum: 10/193f4928ff609a922493f05e2f301f53a3d9b8387e90fc6ab4bc4f78f97272cad000fbdf0f1d23069f67cb35d3d855734ce5a5feab98619aebfc3334be2967c7
   languageName: node
   linkType: hard
 
@@ -4595,13 +4595,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/prop-types@npm:*":
-  version: 15.7.4
-  resolution: "@types/prop-types@npm:15.7.4"
-  checksum: 10/ef6e1899e59b876c273811b1bd845022fc66d5a3d11cb38a25b6c566b30514ae38fe20a40f67622f362a4f4f7f9224e22d8da101cff3d6e97e11d7b4c307cfc1
-  languageName: node
-  linkType: hard
-
 "@types/qs@npm:*":
   version: 6.9.14
   resolution: "@types/qs@npm:6.9.14"
@@ -4616,12 +4609,12 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/react-dom@npm:^18.3.7":
-  version: 18.3.7
-  resolution: "@types/react-dom@npm:18.3.7"
+"@types/react-dom@npm:^19.2.3":
+  version: 19.2.3
+  resolution: "@types/react-dom@npm:19.2.3"
   peerDependencies:
-    "@types/react": ^18.0.0
-  checksum: 10/317569219366d487a3103ba1e5e47154e95a002915fdcf73a44162c48fe49c3a57fcf7f57fc6979e70d447112681e6b13c6c3c1df289db8b544df4aab2d318f3
+    "@types/react": ^19.2.0
+  checksum: 10/616c4a8aee250ea05fb1e7b98e7e00475dd3a6c1c30d7be18b4b93caba832f4203106b3a496a6b147e5acc2da14575eca47bce234c633bca1f8430ef8ffb234a
   languageName: node
   linkType: hard
 
@@ -4634,13 +4627,12 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/react@npm:*, @types/react@npm:^18.3.29":
-  version: 18.3.29
-  resolution: "@types/react@npm:18.3.29"
+"@types/react@npm:*, @types/react@npm:^19.2.15":
+  version: 19.2.15
+  resolution: "@types/react@npm:19.2.15"
   dependencies:
-    "@types/prop-types": "npm:*"
     csstype: "npm:^3.2.2"
-  checksum: 10/1630416dbca8097bc56bb2f7e51208a7d696ed704c58bb3f0470eb982852f1af6d95d5c658eec51d7a5adae6587679d7d81b531b676dfcb405164e32feee6b4b
+  checksum: 10/f77447366a94804feea450568f7ebdadc00155457b4c74240972a73601294b09f45cac4e1a28aa97bc01da9ed130bb5fe9a687835d4da6307d457f92530acc3a
   languageName: node
   linkType: hard
 
@@ -10063,7 +10055,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"loose-envify@npm:^1.1.0, loose-envify@npm:^1.4.0":
+"loose-envify@npm:^1.4.0":
   version: 1.4.0
   resolution: "loose-envify@npm:1.4.0"
   dependencies:
@@ -10109,8 +10101,8 @@ __metadata:
     "@types/mime-types": "npm:^3.0.1"
     "@types/morgan": "npm:^1.9.10"
     "@types/node": "npm:22.19.19"
-    "@types/react": "npm:^18.3.29"
-    "@types/react-dom": "npm:^18.3.7"
+    "@types/react": "npm:^19.2.15"
+    "@types/react-dom": "npm:^19.2.3"
     "@types/react-syntax-highlighter": "npm:^15.5.13"
     "@types/semver": "npm:^7.7.1"
     "@types/smpte-timecode": "npm:^1.2.5"
@@ -10164,11 +10156,11 @@ __metadata:
     p-map: "npm:^7.0.4"
     p-retry: "npm:^8.0.0"
     pretty-bytes: "npm:^7.1.0"
-    react: "npm:^18.3.1"
-    react-dom: "npm:^18.3.1"
+    react: "npm:^19.2.6"
+    react-dom: "npm:^19.2.6"
     react-i18next: "npm:^17.0.8"
     react-icons: "npm:^5.6.0"
-    react-leaflet: "npm:^4.2.1"
+    react-leaflet: "npm:^5.0.0"
     react-lottie-player: "npm:^2.1.0"
     react-markdown: "npm:^10.1.0"
     react-syntax-highlighter: "npm:^16.1.1"
@@ -12108,15 +12100,14 @@ __metadata:
   languageName: node
   linkType: hard
 
-"react-dom@npm:^18.3.1":
-  version: 18.3.1
-  resolution: "react-dom@npm:18.3.1"
+"react-dom@npm:^19.2.6":
+  version: 19.2.6
+  resolution: "react-dom@npm:19.2.6"
   dependencies:
-    loose-envify: "npm:^1.1.0"
-    scheduler: "npm:^0.23.2"
+    scheduler: "npm:^0.27.0"
   peerDependencies:
-    react: ^18.3.1
-  checksum: 10/3f4b73a3aa083091173b29812b10394dd06f4ac06aff410b74702cfb3aa29d7b0ced208aab92d5272919b612e5cda21aeb1d54191848cf6e46e9e354f3541f81
+    react: ^19.2.6
+  checksum: 10/695122e37dec3460311231ff1f9a96368d74457d4ccf60010eaebc08c3e1c47b054c9267b40d98c689ae99d0c29a340acacfd405016a954a4f11613146191e68
   languageName: node
   linkType: hard
 
@@ -12165,16 +12156,16 @@ __metadata:
   languageName: node
   linkType: hard
 
-"react-leaflet@npm:^4.2.1":
-  version: 4.2.1
-  resolution: "react-leaflet@npm:4.2.1"
+"react-leaflet@npm:^5.0.0":
+  version: 5.0.0
+  resolution: "react-leaflet@npm:5.0.0"
   dependencies:
-    "@react-leaflet/core": "npm:^2.1.0"
+    "@react-leaflet/core": "npm:^3.0.0"
   peerDependencies:
     leaflet: ^1.9.0
-    react: ^18.0.0
-    react-dom: ^18.0.0
-  checksum: 10/01cee12dc32e86d0153c989894fdba1c5c50fa41ad8d712352fa616f7b0dd32844aa17bb06c66f7569133675e2946c669090b4c496610cce3fa37c22254ca89f
+    react: ^19.0.0
+    react-dom: ^19.0.0
+  checksum: 10/170bf8d83141c8406fddc8cab41608ec6938efaafa5ae08c2060f9c0739370b84ed61d809c092d9f9ea79461399519f18f1cdf06dcb0e26d61d89eda46fb30be
   languageName: node
   linkType: hard
 
@@ -12332,16 +12323,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"react@npm:^18.3.1":
-  version: 18.3.1
-  resolution: "react@npm:18.3.1"
-  dependencies:
-    loose-envify: "npm:^1.1.0"
-  checksum: 10/261137d3f3993eaa2368a83110466fc0e558bc2c7f7ae7ca52d94f03aac945f45146bd85e5f481044db1758a1dbb57879e2fcdd33924e2dde1bdc550ce73f7bf
-  languageName: node
-  linkType: hard
-
-"react@npm:^19.2.5":
+"react@npm:^19.2.5, react@npm:^19.2.6":
   version: 19.2.6
   resolution: "react@npm:19.2.6"
   checksum: 10/205f0db93bd6c6485f94471d1c3437ae1d410f322297c76186fe4f658f88a6786bb0805e3cf8f330f24d1daa923b6b610ec63960d2461e9201bca64ca8361db9
@@ -12978,12 +12960,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"scheduler@npm:^0.23.2":
-  version: 0.23.2
-  resolution: "scheduler@npm:0.23.2"
-  dependencies:
-    loose-envify: "npm:^1.1.0"
-  checksum: 10/e8d68b89d18d5b028223edf090092846868a765a591944760942b77ea1f69b17235f7e956696efbb62c8130ab90af7e0949bfb8eba7896335507317236966bc9
+"scheduler@npm:^0.27.0":
+  version: 0.27.0
+  resolution: "scheduler@npm:0.27.0"
+  checksum: 10/eab3c3a8373195173e59c147224fc30dabe6dd453f248f5e610e8458512a5a2ee3a06465dc400ebfe6d35c9f5b7f3bb6b2e41c88c86fd177c25a73e7286a1e06
   languageName: node
   linkType: hard